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INTRODUCTION AND OBJECTIVE:Care fragmentation, or the engagement of different health care systems along the continuum of care, has been shown to negatively affect patient outcomes. There is a lack ...

INTRODUCTION AND OBJECTIVE:Osteopontin (OPN) is one of the most important components in the calcium stone matrix. However, the detailed mechanism of OPN-related urinary stone formation remains unkn...

INTRODUCTION AND OBJECTIVE:People with spinal cord injury (SCI) have an increased risk of urinary stone formation and morbidity from the surgeries to remove them. The highest risk of stones has bee...

A 42-year-old woman underwent 131I radiotherapy for thyroid papillary cancer. A focal elevated 131I activity in the right kidney was revealed on the initial whole-body posttherapeutic images, which was located in the region of a renal stone. However, on the follow-up 131I images acquired 6 months later, there was no longer any increased activity in the region of this stone, which had moved into right ureter. Our case indicates that the 131I activity accumulated in the region of urinary stone is due to stagnated radioactive urine rather than due to the stone per se.

Ureteral diverticulum is a rare urinary malformation and can frequently lead to urinary complications. It can be congenital, acquired or an abortive ureteral duplication. Most are treated conservatively. A surgical indication is made in case of symptomatic or complicated diverticulum. It can be congenital, acquired or an abortive ureteral duplication. Most of them are treated conservatively. A surgical indication is given in case of symptomatic or complicated diverticulum. and recurrent total hematuria. Radiological investigations confirmed the diagnosis of congenital ureteral diverticulum complicated with lithiasis.

Background: Most previous studies have demonstrated the possibility of using dual-source dual-energy computed tomography (DSDECT) to distinguish pure stones with high accuracy. While stones are usually composed of a mixture of substances, very few studies have focused on these stone compositions. Objectives: To retrospectively evaluate the diagnostic accuracy of DSDECT in predicting the composition of mixed urinary calculi in vivo compared to the postoperative infrared spectroscopy (IRS) for stone analysis. Patients and Methods: We retrospectively included 111 patients with 117 mixed urinary stones, detected by IRS, who underwent DSDECT between June 2018 and March 2020. Patients diagnosed with urolithiasis were examined by DSDECT preoperatively. The final stone composition was detected by IRS in vitro postoperatively. Also, the stone composition predicted by DSDECT was compared to the IRS results, known as the reference standard. Results: According to the results of IRS, 117 mixed urinary calculi, composed of a main constituent and minor admixtures, were divided into four groups: calcium oxalate (CaOx)-hydroxyapatite (HA) (n = 70); HA-CaOx (n = 36); uric acid (UA)-CaOx (n = 8); and cystine (CYS)-HA (n = 3). The accuracy of DSDECT in predicting different components of mixed urinary stones was 68.4%, 64.1%, 97.4%, and 97.5% for the CaOx-HA, HA-CaOx, UA-CaOx, and CYS-HA stones, respectively. The imaging characteristics of different mixed urinary stones, as shown by DSDECT, revealed that the CaOx-HA ratio value was lower than that of HA-CaOx (1.59 ± 0.11 vs. 1.66 ± 0.22; P < 0.05). Meanwhile, the computed tomography (CT) values of CaOx-HA under 150 kV were higher than those of HA-CaOx (915.41 ± 226.84 vs .799.56 ± 252.01; P < 0.05). Conclusion: Although DSDECT has a relatively low accuracy for predicting the components of CaOx-HA and HA-CaOx in vivo, its combination with the measured ratio and CT values may help differentiate these stones.

Background ESWL is still considered as the first favorable therapeutic option for urinary stone disease with acceptable effectivity. However, factors associated with favorable outcome have not been widely studied in pediatrics due to the small number of urinary stone prevalence. The aim of this study is to evaluate the factors associated with the success rate of pediatric ESWL in our center according to immediate stone-free rate and 3-month stone-free rates. Methods This is a retrospective cohort study of children less than 18 years who had ESWL for urolithiasis from January 2008 until August 2015. Patient’s characteristics including age, gender, BMI, stone location, stone length, stone burden, stone opacity, and number of ESWL sessions were gathered from the medical record. Nutritional status was determined according to the Centers for Disease Control and Prevention BMI curve. The outcome of this study was the factors related to the success rate in pediatric ESWL. Results Extracorporeal shock wave lithotripsy was done for 36 patients and 39 renal units (RUs) with mean age of 13.7 ± 4.3 years old, height of 1480 ± 16.0 cm, and BMI of 20.0 ± 3. Of 36 patients included, 39 renoureteral units (RUs) and 46 ESWL sessions were recorded. The mean overall treatment was 1.2 ± 0.5 sessions with mean stone length of 11.1 ± 6.3 mm and stone burden of 116.6 ± 130.3 mm2. Within 3 months of follow-up, we recorded that the overall 3-month success rate was 100%, while the overall 3-month stone-free rate was 66.7%. Stone length (p p p p p p = 0.001) were found to be significantly associated with immediate success and 3-month stone-free status, respectively. Conclusions ESWL is an effective and safe modality to treat pediatric urolithiasis cases. Stone length, stone perpendicular length, and stone burden were found to be associated with immediate success and 3-month stone-free status after pediatric ESWL treatment.

The prevalence of kidney stone disease is increasing worldwide. The recurrence rate of urinary stones is estimated to be up to 50%. Nephrolithiasis is associated with increased risk of chronic and end stage kidney disease. Diet composition is considered to play a crucial role in urinary stone formation. There is strong evidence that an inadequate fluid intake is the major dietary risk factor for urolithiasis. While the benefit of high fluid intake has been confirmed, the effect of different beverages, such as tap water, mineral water, fruit juices, soft drinks, tea and coffee, are debated. Other nutritional factors, including dietary protein, carbohydrates, oxalate, calcium and sodium chloride can also modulate the urinary risk profile and contribute to the risk of kidney stone formation. The assessment of nutritional risk factors is an essential component in the specific dietary therapy of kidney stone patients. An appropriate dietary intervention can contribute to the effective prevention of recurrent stones and reduce the burden of invasive surgical procedures for the treatment of urinary stone disease. This narrative review has intended to provide a comprehensive and updated overview on the role of nutrition and diet in kidney stone disease.

Bacterial infection has long been recognized to contribute to struvite urinary stone deposition; however, its contribution to the development of chronic kidney stones has not been extensively investigated. In the present study, we hypothesized another possible method of bacteria contributing to the formation of calcium oxalate (CaOx) that accounts for the biggest part of the kidney stone. Bacteria may play important roles by influencing renal Ca2+-related ion channel activities, resulting in chronic inflammation of the kidney along with rapid aggregation of stones. We examined the correlation among infection-promoted CaOx kidney stones and alterations in Ca2+-related ion channels in an animal model with experimentally induced Proteus mirabilis and foreign body infection. After the bladder was infected for 7 days, the data demonstrated that stones were presented and induced severe renal tubular breakage as well as altered levels of monocyte chemoattractant protein-1, cyclooxygenase-2, osteopontin, and transient receptor potential vanilloid member 5 expression, reflecting responses of kidney ion channels. Monocyte chemoattractant protein-1, osteopontin, and transient receptor potential vanilloid member 5 expression was significantly downregulated over time, indicating the chronic inflammation phase of the kidney and accelerated aggregation of CaOx crystals, respectively, whereas cyclooxygenase-2 exhibited no differences. These results indicated that bacterial infection is considerably correlated with an alteration in renal Ca2+-related ion channels and might support specific and targeted Ca2+-related ion channel-based therapeutics for urolithiasis and related inflammatory renal damage.

The pressed powder sample is a common method for elemental analysis using X-ray fluorescence analysis whereas suitable light hydrocarbon materials should be added to the sample as a binder. The present study demonstrates the applicability of using different commercial binders for elemental analysis of urinary stone samples. In order to confirm the obtained results, a comparison with pure chemical grade binders was presented. Different commercial and pure binders were tested for quantitative elemental analysis of urinary stones, namely, cellulose, starch, wax, and urea. Energy dispersive X-ray fluorescence (EDXRF) was used for elemental analysis. Differential thermal analysis was used to estimate the loss on ignition (LOI) in the urinary stone samples. The signal to background ratios (I/IB) of the different detected elements in the commercial and pure binders were calculated, compared, and studied at eight different photon energies starting from 2.5 up to 37 keV. Standard-less quantitative analysis method based on the fundamental parameter approach was applied for elemental analysis of selected urinary stones. The commercial and low-cost binders could be an excellent alternative binder for urinary stone analysis using energy dispersive X-ray fluorescence. The commercial binders could provide an advantage as pure chemical grade binders or even better especially at photon energy higher than 10 keV. The best commercial binder candidate was found to be the wax. The quantitative analysis results using commercial and pure chemical grade binders give good agreement results, which indicate the applicability of commercial binders for quantitative elemental analysis of urinary stones in the form of pressed powder samples.

The present study aims to biochemically analyze the fluid samples containing stone dust taken during the perioperative period to determine the role of fluid in the prediction of stones in patients treated with ureterorenoscopic procedures. Our secondary aim is to investigate the role of both fluid analysis and stone analysis in predicting the results of the metabolic analysis. Comparative analyses were performed using fluid samples containing stone dust from 93 patients. Biochemical analysis of fluid containing stone dust was conducted; stone fragments were examined at a separate location using X-ray diffractometry(XRD). Metabolic analysis was performed to patients who provided stone-free status 1 month later. The results of chemical analysis were compared with the results of the XRD analysis. Patients’ stone type was determined with high accuracy using biochemical analysis. Differences were noted in ten patients following biochemical analysis and XRD analysis. Biochemical analysis predicted metabolic disorders in more patients than XRD analysis, particularly for those patients with multiple stone compositions. However, no significant differences between the results of biochemical and XRD analysis methods were found (κ = 0.27; p = 0.002). Moreover, biochemical analysis results revealed metabolic disorders in five patients; these findings were missed by XRD analysis. Biochemical analysis of fluid taken perioperatively during ureterorenoscopic laser lithotripsy to treat urinary system stone disease was found to determine stone composition with high accuracy. Biochemical analysis of fluid samples taken during the perioperative period is, thus, an easy, reliable and cost-effective test to assess stone composition in patients undergoing ureterorenoscopic procedures.

Introduction and Objectives: The Moses effect (ME) was described >30 years ago during normal laser functioning in a fluid medium. Recently, a laser device equipped with a pulse-modulating system called Moses™ technology (MT; Lumenis®) was marketed for both stone lithotripsy and prostate endoscopic surgery. We aimed to perform a literature revision of ME from a historical perspective up until its present-day applications. Evidence Acquisition: A search of Medline, PubMed, and Scopus was performed to identify articles published in English within the past 30 years addressing both ME and MT in relation to their urologic applications. Relevant studies were then screened, and the data were extracted, analyzed, and summarized. The preferred reporting items for systematic reviews and meta-analysis criteria were applied. Results: ME was first described in 1986 during endovascular laser tissue ablation. During the late 1980s and the early 1990s, the interest raised around ME led to its characterization and better definition. Despite this initial interest, ME gradually disappeared from the focus of researchers and clinicians. In 2017, MT was launched on the market, although postmarketing comparative efficacy and safety data are lacking. Conclusions: Although ME had been described and characterized during normal laser functioning >30 years ago, only very recently it began to regain some consideration after the marketing of MT, whose clinical outcomes are still awaited.

Purpose: Holmium laser lithotripsy is a common modality used to fragment urinary stones during ureteroscopy. Laser energy deposited during activation produces heat and potentially causes thermal bioeffects. We aimed to characterize laser-induced heating through a computational simulation. Materials and Methods: A finite-element model was developed and used to estimate temperature in the urinary tract. Axisymmetric models of laser lithotripsy in a renal calyx, the renal pelvis, and proximal ureter were created. Heat generation by laser and heat transfer were simulated under different laser powers between 5 and 40 W. Irrigation fluid flow was introduced at rates between 0 and 40 mL/min. The model was validated by comparison with previous in vitro temperature data in a test tube, then used to calculate heating and thermal dose in the three tissue models. Results: Simulated temperature rises agreed well with most in vitro experimental measurements. In tissue models, temperature rises depended strongly on laser power and irrigation rate, and to a lesser extent on location. Injurious temperatures were reached for 5–40 W laser power without irrigation, >10 W with 5 mL/min irrigation, 40 W with 15 mL/min irrigation, and were not found at 40 mL/min irrigation. Tissue injury volumes up to 2.3 cm(3) were calculated from thermal dose. Conclusions: The results suggest a numerical model can accurately simulate the thermal profile of laser lithotripsy. Laser heating is strongly dependent on parameters and may cause a substantial temperature rise in the fluid in the urinary tract and surrounding tissue under clinically relevant conditions.

The present study concerns an important topic regarding the search for new, improved, and effective methods of preventing the development of infectious urinary stones. In this article, the effect of tetrasodium pyrophosphate (TSPP) on the formation of a poorly crystalline and amorphous precipitate in artificial urine in the context of infectious urinary stone formation is studied. The spectrophotometric results suggest that TSPP presence shifts the formation of the poorly crystalline and amorphous precipitate (PCaAP) toward lower pH, which means that PCaAP is formed earlier. In other words, TSPP promotes the formation of PCaAP. Additionally, TSPP causes the formation of calcium pyrophosphate. These results are confirmed by X-ray diffraction and energy dispersive X-ray studies. The experimental results obtained are explained on the basis of theoretical chemical speciation analysis of chemical complexes formed in artificial urine.

PURPOSE This study aimed to prospectively compare the image quality and visibility of urinary stone on computed tomographic (CT) images at multiple radiation exposure levels from the same patient reconstructed with sinogram-affirmed iterative reconstruction (SAFIRE). METHODS This study included 760 patients with urinary stone who underwent CT with simultaneous acquisition at 6 exposures per patient (100% filtered back projection, 75%, 50%, 37.5%, 25%, and 12.5% SAFIRE). Two radiologists independently assessed overall image quality, noise, and stone visibility by using a 5-point scale. Quantitative measurements, including the CT number, image noise, signal-to-noise ratio, contrast-to-noise ratio (CNR), and corresponding figure of merit (FOM), were compared for 100% versus 5 other radiation doses. RESULTS Qualitative overall image quality, noise, and stone visibility according to the location were not inferior at 37.5% exposure compared with 100% exposure, except for the visualization of smaller stones

Objective To evaluate the accuracy of semiautomated segmentation of urinary stone size in computed tomography (CT) compared with manual measurement. Materials and Methods A total of 103 patients (32f, 71m ; mean age 52 years±18 that were diagnosed with urolithiasis and collected stones received standardized ex vivo CT-scans and radiography of the stones. Stone size was segmented semiautomatically using commercial software (syngo.via, Siemens, Germany) and compared with manual caliper measurement on digital radiography. Results Mean size was 4.4 mm in CT and 4.6 mm in radiography. Depending on number of stones analyzed per patient, estimation of stone size showed moderate to excellent correlation for both methods. There was no significant difference in overall size measurement. Conclusion Semiautomatic segmentation of urinary stone size in CT is possible and reduces measurement errors, allowing more precise estimation especially for smaller concrements. Neighboring stones may hamper segmentation of stone size.

We examined the mechanism of urinary stone formation by analyzing the matrix proteins in a urinary stone with two layers composed of different crystals. Micro-area X-ray spectrometry and infrared spectroscopy revealed calcium oxalate monohydrate in the outside and uric acid in the inside. We also examined the interface. After the outside, inside, and interface parts were separated, proteomic analysis identified 48, 7, and 4 matrix proteins, respectively. Urinary stones with two layers are considered to have grown under different conditions. The matrix proteins in each part differed among the crystal components and may reveal the stone-generating process. The proteins in the interface likely function to enlarge the stone via the addition of different crystals.

We aimed to evaluate the reliability of a portable device that applies Raman spectroscopy at an excitation wavelength of 1064 nm for the post-operative analysis of urinary stone composition. Urinary stone samples were obtained post-operatively from 300 patients. All samples were analyzed by the portable Raman spectroscopy system at an excitation wavelength of 1064 nm as well as by infrared spectroscopy (IR), and the results were compared. Both Raman spectroscopy and IR could detect multiple stone components, including calcium oxalate monohydrate, calcium oxalate dihydrate, calcium phosphate, uric acid, cystine, and magnesium ammonium phosphate hexahydrate. The results from 1064-nm Raman analysis matched those from IR analysis for 96.0% (288/300) of cases. Although IR detected multiple components within samples more often than Raman analysis (239 vs 131), the Raman analysis required less time to complete than IR data acquisition (5 min vs 30 min). These preliminary results indicate that 1064-nm Raman spectroscopy can be applied in a portable and automated analytical system for rapid detection of urinary stone composition in the post-operative clinical setting. Chinese Clinical Trail Register ID: ChiCTR2000039810 (approved WHO primary register) http://www.chictr.org.cn/showproj.aspx?proj=63662 .

Background: Urinary tract calculus formation can be prevented by identifying molecules and metabolic disturbances that affect this process. Osteoprotegerin (OPG), a cytokine of the TNF receptor superfamily, has been demonstrated to mediate vascular calcification and intimal calcification. Endothelial injury and oxidative stress are known to play a role in urolithiasis in the form of Randall’s plaques. Objectives: The present study aimed to compare 24-h urinary and serum OPG levels of patients with and without urolithiasis. Methods: In this case-control study, 24-h urinary levels of OPG (pg/mL), serum levels of OPG (pg/mL), and creatinine (mg/dL) were measured in both groups. Urinary and serum levels of OPG were determined by enzyme-linked immunosorbent assay (ELISA) using human OPG kits. Results: Mean serum creatinine was 0.86 ± 0.21 mg/dL in the case group and 0.77± 0.16 mg/dL in controls. The difference in the mean serum OPG levels between the cases (227.13 ± 98.02 pg/mL) and controls (47.28 ± 29.61 pg/mL) was highly significant (P value < 0.0001). The difference in the mean 24-h urinary OPG levels between the cases (156.12 ± 174.31 pg/mL) and controls (9.32 ± 23.72 pg/mL) was highly significant (P value < 0.001). Conclusions: There were significantly higher levels of OPG in serum and 24-h urine samples of cases than in controls. Hence, it requires further large studies to make OPG a diagnostic and prognostic marker.

A total of 1520 patients with urinary stones from central China were collected and analysed by Fourier transform infrared spectroscopy between October 1, 2016 and December 31, 2019. For all patients, age, sex, comorbidities, stone location, laboratory examination and geographic region were collected. The most common stone component was calcium oxalate (77.5%), followed by calcium phosphate (8.7%), infection stone (7.6%), uric acid (UA) stone (5.3%)and cystine (0.9%). The males had more calcium oxalate stones (p

Introduction: In the last years due to miniaturization of endoscopic instruments and percutaneous surgery, endourology has become very popular in paediatric urinary stone managment. We reported our single-centre experience in retrograde endoscopic procedures in children. Results and complications of URS/RIRS are discussed. Materials and methods: We retrospectively reviewed our experience in patients ≤ 16 years old affected by urinary stones who underwent URS/RIRS procedures performed by two surgeons with expertise in endourology. A total of 30 renal Units (RUs) underwent endoscopic procedures (URS, RIRS or both). Surgical complications according to the ClavienDindo’s classification and stone-free rate were evaluated at 3 months follow-up. Success of URS was defined as stone-free status after single procedure while RIRS success rate was considered as presence of residual stone fragments smaller than 4 mm at first procedure. Results: The mean age of our patients was 8 years, range 2- 16 years. A total of 30 renal units (RUs) underwent 40 endourological procedures (23 URS and 17 RIRS; 10 children underwent both procedures at the same time). 17/30 (56.6%) RUs were pre-stented before surgery. The stone-free status was achieved in 23/30 renal units treated, with a 76.6% success rate. The remaining 7 patients had residual stones greater than 4 mm and underwent further treatments. After a second surgery the stone-free rate turned out to be 93.3% (28/30 renal units). Conclusions: Rigid and flexible ureteroscopy (URS/RIRS) is a reliable technique for treatment of < 2 cm urinary stones in paediatric age group. It shows low rate of major complications and promising results in terms of stone-free rate.